Apparatus for discharging centrifugal machines



May 16, 1933. E R B 1,909,188

APPARATUS FOR DISCHARGING- CENTRIFUGAL MACHINES Filed April 15, 1931heetg-Sheet l 2 fizvendz atiorznzg E. ROBERTS May 16, 1933.

APPARATUS FOR DISCHARGING CENTRIFUGAL MACHINES Filed April 15, 1931 2Sheets-Sheet 2 Patented May 16, 1933 UNITED STATES PATENT OFFICE EUGENEROBERTS. OF HASTINGS, NEW. YORK, ASSIGNOR TO THE WESTERN STATES .MACHINECOMPANY, OF SALT CITY, UTAH, A CORPORATION .OF UTAH APPARATUS FORmscmmsme CENTRIFUGAL MACHINES Application filed April 15,

" and having a bottom discharge opening through which the walled upsolid material may be discharged to permit reloading the basket with anew charge to be centrifugally treated.

One object of the present invention is to provide means forautomatically controlling the discharging operation without requiringthe attendance of the operator, so that as soon as the charge ofmaterial in the basket has been properly centrifuged the solid residuewalled up on the interior of the basket may be discharged through thebottom of the basket without danger of breakin or injuring theapparatus, so that the mac ine may be emptied to receive the next loadwhether the next load is automatically charged into the machine orcharged by hand control.

\Vith such objects in view the invention embraces, generally speaking, adischarging apparatus comprising a carrier head mounted inside thebasket and provided with plows or disrupting means for breaking down anddischarging the walled up material through the bottom of the basket,combined with suitable retarding and lifting mechanism by which thedischarging plows may be actuated through association with controllingand actuating mechanism that is coordinated with the centrifugal drivingand braking mechanism, whereby upon the cutting off of the drive and thesetting of the brake, the discharging apparatus automatically actthrough itsassociation with such driving and braking mechanism, todischarge thematerial through the bottom of the centrifugal.

These and other features of my invention will be described in thefollowing specification and will be defined in the claims heretoannexed.

In the accompanying drawings I have illustrated a well known type ofgyratory centrifugal equipped with one form of automatically controlleddischarging apparatus 1931.. Serial in. 530,224.

embodying the principles of my invention.

In said drawings 7 Fig. 1 is a sideelevation, partly in section,illustrating the application of my improvement to such a centrifugal.

Fig. 2 is a plan. View, partly in section, of the mechanism shown inFig. 1 on a plane slightly above the level of the centrifugal basket andcurb.

'Fig. 3 is an enlarged detail view of the overhead valve through whichthe actuating mechanism for lifting the head is energized. to raise thehead when starting the machine in operation.

Fig. 4 is a detail view showing the automatic control mechanism mountedon the main air-cylinder as viewed in the plane of the broken line XX ofFig. 1.

Fig. 5 is a detail View showing in elevation, as viewed in the plane YYof Fig. 4, the ratchet controlled means by which the main valve lever isactuated on alternate upward strokes of the piston rod of the mainchamber.

Fig. 6 is a detail View showing in cross section, on plane Z-Z of Fig.4, the ratchet and valve mechanism carried on the head of the mainpiston.

Fig. 7 is a detailed view'on the plane VV\V of Fig. 4 showin theautomatically shifting, lifting and W1 nism.

The discharging mechanism is here shown as applied to a well known typeof centrifugal machine embracing the usual gyratory central drivingshaft-1, to whose lower end the basket 2 is firmly secured by means of aradial spider 4 fastened in the central discharge opening in the bottom3 of the hasket. surrounded with the usual stationarv curb or casing 6,which collects the centrifugally expelled liquid. The center ofgyration, or suspension, in this case is at a in the usual socketedhanger A and there is provided a ve control mecha- The basket has theusual top ring '5 to the low speed and the high speed driving positions,in both of which positions of course the brake is released. The aboverecited construction is well known in the art and is illustrated in myPatent-s No. 1,719; 132 and No. 1,758,901, the brake and drivingmechanism being omitted as forming no part of the present invention andas well understood in the art.

On the central driving shaft 1 is slidingly mounted a carrier head 10provided. at its upper end with an annular grooved clutch spool 10, andcarrying on its bottom lateral extension 10 a pair of hollow bosses 12in which is pivotally mounted at 11 laterally projecting plows 11 whichcan swing outward close to, but not to exert pressure against, theperforated lining or screening on the inside of the basket wall. Sincethis carrier head is supported by the rotary shaft and the rotarybasket, it normally partakes of its rotary movement, although being freeto rotate in relation to the basket and shaft if retarded by anyappropriate retarding means. The lateral extension 10, which serves as asupport for thedischarger plows, may also serve when given a circularform to art as a closure for the discharge opening occupying the centralpart of the basket bottom 8. The clutch spool. 10 at the top of thishead is adapted to be engaged by a pair of opposed clutch blocks 12,which are pivotally mounted in supporting and actuating arms 13 that arefulcrnmed about a common pivot 14- in the lifting head 15, whichprojects from the inner end of the lifting lever 16. This lifting lever16 is pivotally mounted at 17 in a pair of links 18 which are fulcruniedat 19 on top of the curb. The lever also has an outward extension 16which acts as a power arm for lifting the head by its actuating means,which in this case comprises a compressed air cylinder 31 pivotallymounted on a fixed bracket 30 and containing a slide piston 32 to whichis secured the piston rod having a pivotal engagement with the outer endof the power arm 16 of the lifting lever. There is a smaller compressedair cylinder 20 containing a piston 20, to the inner end of whose pistonrod 20" is pivotally attached a pair of toggle levers or links 17 whichare pivotally connected with the outer ends of the clutch levers 13, sothat when the piston 20 is forced inward under the pressure of air thetoggle links are expanded to force the clutch blocks or shoes 12 intofirm engagement with the clutch spool formed at the head of thevertically slidable carrier head 10. A return spring 21 yields under theair pressure to allow the piston 20 to move inwardly to grip the clutchshoes against the carrier head, while acting to return the piston whenthe air pressure behind it is relieved.

It will be understood that pressing the clutch blocks 12 into brakingengagement with the spool end of the carrier head acts to produce africtional retardation of the head and of the plow or plows carried byit, so that the more slowly revolving plows dig out and discharge thewalled up material which is revolving faster than are the plows. l/Vherea Hat bottom basket is used, as illustrated in the present drawings,with a bottom closure or valve the latter must be lifted from the bottomof the basket to a more or less open position to allow the sugar to passthrough the bottom opening. Consequently, it is preferable in such caseto lift the carrier head 10 before effecting such serious retardation ofthe head, the plow being provided with a lost motion connection, asshown in Fig. 1, permitting the bottom valve to lift a short distancebefore the plow raises. Thereafter, the lifting and retardation of theplow serves to shear away the walled up material and discharge itthrough the bottom discharge opening. After the carrier head and plowsare lifted to the topmost position, the compressed air supply is cut offand the valve and lifting head allowed to drop to low position to closethe botton'i discharge opening, the compressed air confined behind thepistons being vented by serving as a cushion for preventing shock whenthe bottom discharge valve and the head are dropped. In my pendingapplication, Serial No. 516,372, the above described mechanism wasdisclosed and explained in detail, but in that case the control of themechanism was through manual maniymlation, which required the attendanceof the operator.

In the present case the different mechanism for retarding the carrierhead to produce a differential rotation and the lifting and the returnof the carrier head is effected by a control mechanism that i. gov--elned by the starting and braking of the centrifugal and thisself-acting control will now be described in detail, it being understoodthat the present application of power for actuating these movements isthrough the medium of compressed air, although I do not limit myself tosuch an actuating medium in the practice of this invention.

The compressed air supply for present purposes is furnished through thesupply pipe 37 from which lead two separate branches 40 and 36 whoselower ends are connectedv by flexible hose connections 4W and 36 withthe actuating mechanism in the manner now to be described.

At approximately the suspension level of the centrifugal, the air pipe40 is provided with a valve 41, which is of the rocker type providedwith an actuating arm a2 which occupies the rear-most position of itsmove ment when the valve is closed and which moves tothe forwardposition to open the valve to admit compressed air into the cylinder 31above the piston 32.

As it is preferred to open the valve when moving the starting andbrake-releasing lever a to first or low speed position, while stillpermitting said lever thereafter to be moved forward to high speedposition, I provide an over-the-center throw by pivotally connectingwith the valve arm 42 a pivoted link 43 having a compression or thrustspring 44, which has a double action, namely, as soon as the pivotalcenter has passed to one side of the straight line position the springquickly throws the valve to its extreme position on that side and thesame action takes place when it is moving in the opposite direction. Thepivot pin connecting the toggle couple 42 and 43 extends through a slot45 in the link 46, which is pivotally attached to the centrifugalcontrol arm a. -With the toggle couple in the real-most or right handposition, as shown in Fig. 1, and with thecontrol lever in its rearwardnon-starting and brake-setting position, the connecting pin occupies therear part of the slot 45, but when the lever c is thrown forward tosecond speed position, also releasing the brake, the movement of thelink 46 is sufiicient to pull the actuating pin. of the toggle beyondthe dead center line, thus allowing the thrust spring 44 to force thetoggle to the left hand or forward position. As the link 46 has movedforward, this movement leaves sufficient length of the slot behind thepin in its forward position to allow movement of the starting lever fromlow speed to high speed.

position.

Vhen the control lover of the centrifugal moves back to rearwardposition at the time of cutting off the power and setting the brake, theforward end wall of the slot 45, pushes the toggle couple rearwardlybeyond the dead center allowing the toggles to return to the positionshown in Fig. 1, thereby closing the valve and opening the vent.

It should be understood that the air duct 40 leading into the upper endof the cylinder supplies air only for the purpose of raising the liftinghead (when disengaged from the clutch spool) out of the basket to idleposition in order to get it out of the way when loading and operatingthe centrifugal, the carrier head beingleft in bottom closing position.In Fig. 3 is shown in dotted lines the position of the valve arm 42 whenthe centrifugal is in normal operation, during which time the compressedair supply through pipe 41keeps the piston 32 at the bottom of itscylinder.

However, when the control lever 0 is moved rearwardly into position tocut off the power and apply the brake, the valve arm is moved to fullline position in Fig. 3, thereby cutting off the air supply and openingcommunication with thevent passage 41", whose capacity can be regulatedby the needle valve 41 to allow the lifting head to drop gently to itslowermost. position where the clutch blocks are on a level with thespool 10*. When the lifting head drops into the basket its outerextension 16, connected to the piston rod, raises until a projectingprong or finger 33 carried by the arm 16 engages a registering finger ofthe star wheel 38 thereby lifting the star wheel and the sleeve 38mounted on the valve opening slide rod 37. The lower end of this valverod 37 is pivotally connected with an arm secured to the rock valve 34and the lifting of this arm 35 opens com municationthrough the valvebetween the air supply tube 36 and an outlet tube 22, which leads to thehead of the cylinder 20. Therefore, by the lifting of the valve arm 35air is admitted first through tube" 22 behind the piston 2O to thecylinder 20, thus forcing that piston inwardly and thereby engaging theclutch blocks 12 with the retarding spool 10*. As soon as the piston 2Ohas moved inwardly far enough to engage the clutch blocks with saidspool, it uncovers a lateral port in the cylinder 20, which is connectedwith an inlet opening in the head of the cylinder 31 to allow part ofthe compressed air to escape into cylinder 31 above the piston 32, thusforcing downthe piston 32, which is the lifting piston, while at thesame time continuing toexert braking or retarding pressure through theclutch blocks upon the spool 10*. These two pistons continue to functionuntil the upwardly moving plows have reached their topmost position withthe carrier head 10 inasmuch as the very small vent in the valve 41 hasno appreciable effect in proportion to the volume of compressed airsupply to the respective cylinders through the valve 34 and the conduits22 and 23.

To prevent the prong 33 from engaging a tooth of the star wheel 38 onthe next downward traverse of the head, provision has been made forpartial rotation of the star wheel 38 to bring one of the intermediatespaces or notches into registry with the lifting member 33 so that thelifting member 33 passes up between two fingers of the starwwheelwithout lifting it and therefore without opening the valve 34. 7

It is therefore apparent that the opening of the valve 34 is effectedonly on each al-' ternate upward stroke. The first upward stroke iseffected when the idling head drops into its lowermost positionfollowing the return of the centrifugal control lever c to power-idling,brake-setting position and acts as above explained to open valve 34 toapply power to the plow actuating or the discharger mechanism. Thesecond upward stroke of the piston 32 merely allows the carrier head andthe lifting head to drop downward after they have performed their work.

Any suitable form of mechanism may be employed to secure thisalternating opening of the valve 34 on the upward stroke. In the presentcase I have employed rotatable tubular sleeve 38, mounted on the sliderod 37, which is pivotally connected with the valve arm to have rotationthereon, but anchored between top and bottom collars to prevent slidingmovement of the sleeve on said valve actuating rod. At the upper end ofthis sleeve is secured the star wheel 38 with ample spaces between theperipheral teeth or prongs. At the lower end of this sleeve is secured aratchet wheel 38" having twice as many teeth as the star wheel andbeneath the sleeve pivoted on the valve rod 37 is a ratchet arm 38carrying a pawl 58 at its rear end and provided with a camlike surfaceat its forward end adapted to engage a downwiuidly project-ing blade 33whose lower end is tapered as shown in Fig. 5 to engage and rota theratchet arm. 38 through the arc of one tooth of the ratchet wheel 38 ina clockwise direction. The ratchet arm 38 is returned to initialposition, when freed of the cam member 33, by means of a spring 38", asshown in Fig. 6.

It will therefore be seen that each time the arm 16 moves downward theattached cam member 33" which it carries engages and moves the ratchetone tooth. One such movement moves a tooth of the star wheel intoalignment with the lifting prong 33, while on the next downward movementthe ratchet moves the sleeve and star wheelv to bring a notch in thestar wheel in rcgistr with the lifting prong and this alternating actionis repeated indefinitely.

Since the valve 534i is open when arm .25 is in raised position, it willbe closed by the depression of said arm by means of a pin 33 projectingfrom the upper end of the piston rod when the piston descends to its lowposition.

Preferably in the case of a flat bottom basket such as shown in thedrmvings, the head should drop before the cei'itrifugal comes to a stopin order to allow the discharger to receive any sugar that may l arefallen upon the bottom, but in the case of a scli lischarging basketwith a steeply in clined frusto-conical bottom this might not be thecase. The speed of dropping umy be controlled through adjustment of theair vent.

What I claim is:

l. The combination with a gyratoi trifugal, including driving and brameans, whose basket is provided tral discharge opening in the bottom, ofa discharging apparatus embracing a plowcarrying head slidably mountedon the centrifugal shaft, and a discharging plow arranged thereon to cutdown the walled up material in the basket, means for frictionallyclutching and retarding said head after rotation of the or trifugal hasbeen retarded by application of its brake, means for lifting said headactuatin means for operating said clutching and said lifting means whenthe drive control of the centrifugal has been cut olf and the brakeapplied to cause the plow to discharge the solid walled up matrialthrough the bottom of the basket.

2. The combination with a gyratory centrifugal, including driving andbraking means, whose basket is provided with a central discharge openingin its bottom, of a discharging apparatus embracing a plow and itssupport mounted loosely on the basket shaft inside the basket to revolveon the shaft, means actuated after the setting of the centrifugal brakefor retarding the revolution of the plow to cause it to lag behind therctarded centrifugal and for lifting it toward the top of the basket,and means coordinated with the centrifugal driving and braking mechanismfor energizing said retarding and lifting mechanism to cause the plow toshear away the walled up material inside the basket to discha it throughthe bottom of the basket.

3. The combination with a gyratory centrifugal, including driving andbraking means, Whose basket is provided with a coin tra l dischargeopening in its bottom, of a discharging plow mounted inside the basketto permit it to revolve with the basket, a support therefor looselymounted on the basket shaft, means for frictonally engaging said supportto retard its revolution in relation to the basket, said retarding meansbeing controlled through the agency of the brake setting mechanism ofthe centrifugal after the brake has been applied to retard thecentrifugal to actuate the plow retarding means and thereby causedischarge of the solid material in the basket through the bottom openingtherein.

i. The combination with a gyratory centrifugal, of a discharger plow, asupporting head tl'k-n'efor loosely mounted on the shaft of thecentrifugal, a retarding clutch movable into braking engagement withsaid support to cause the support and plow to revolve at slower speedthan the basket, an air actuated piston for gripping said clutch uponsaid supporting member, and an air controlled alvc energized through theaction of the brake setting mechanism to admit air to the piston tocause said clutch to operate when the brake is applied to thecentrifugal.

5. The combination with a centrifugal whose basket provided with acentral opening in its bottom, of discharging apparatus embracing adischarger plow, a supportlng head therefor loosely mounted on thecentrifugal shaft to permit independent sliding and rotating movementsin relation thereto and normally revoluble with the basket means ada)tGCl to frictionall. en a e and retard said plow support, means forlifting said plow support, separate coordinated power actuated membersfor actuating, respectively, said retarding means and said liftingmeans, said actuating members being controlled through the centrifugalstarting and braking mechanism.

6. i The combination with a centrifugal, including driving and brakingmeans, whose basket is provided with a central opening in its bottom, ofdischarging apparatus cinbracing a discharger plow, a supporting headtherefor loosely mounted on the centrifugal shaft to permit independentsliding and rotating movements in relation thereto, said head beingconstructed to act as a closure for the bottom opening, means adapted tofrictionally engage and retard said plow support, means for lifting saidplow support, separate coordinated power actuated members for actuating,respectively, said retarding means and said lifting means,

, tom discharge opening,

said actuating members being energized by the setting of the centrifugalbraking mech anism.

7. The combination with a centrifugal whose basket is provided with acentral bottom discharge opening, of discharging apparatus embracing aplow supported head and a plow mounted inside the basket to normallyrevolve therewith, means for retarding the revolution of the head andplow relative to the revolving basket, said means including an airactuated piston and valve mechanism by which the action of the pis tonis controlled, said valve mechanism being associated with mechanismcontrolling the starting and stopping of the centrifugal to render saidretarding means active and inactive at predetermined stages in the ooration of the centrifugal.

8. The combination with a Centrifu whose basket is provided with acentral botof discharging paratus comprising a discharger device mountedinside the basket and normally revoluble therewith, separate means forretarding the revolution of the discharger and for raising it from thebottom of the basket,

an actuating piston for effecting retardation of the discharger, asecond piston for can. g the lifting of the discharger, an air controlvalve operated through the medium of mech anism that controls thedriving and braking of the centrifugal to admit con'ipressed air to eachof said pistons in a predetermined timerelation and thereby cause thedischarger to discharge the material.

9. The combination with a centrifugal whose basket is provided with acentral bottom discharge opening, of discharging apparatus embracing adischarger head and plow mounted in the basket, separate air actuatedpistons for operating said discharger and plow to discharge materialthrough the basket bottom, coordinated valve mechanism co-operativelyassociated with mechanism that controls the starting and stopping of thecentrifugal and acting to admit compressed air to said pistons foroperating the discharger and to permit the returnof the discharger toinactiveposition at predetermined stages in the operation of thecentrifugal. j

10. The combination with a centrifugal whosebasket is provided with acentral bottoi'nj tlischarge opening, of discharging apparatus embracingV a revoluble discharger head and? plow mounted inside the basket,actuating means comprising separate pistons for operatingsaid plow andcausing itto traverse the basket vertically, selfacting valve mechanismfor admitting compressed air to said pistons andcutting it offtherefrom,- said valve mechanism being rendered active by the settingofzthe'eentrifugal brake.

11. A discharger apparatus for sugar centrifugals embracing, a plowsupporting head and a plow adapted to be revolubly mounted in thecentrifugal basket, a lifting lever pivotally mounted outside the basketand having friction shoes for engaging and retarding a head and forraising and lowering the head, a' retarding shoe actuating piston, aseparate piston for actuating the lever, 00- ordinated valve mechanismfor controlling the supply of compressed air to said pistons to causeoperation ofthe discharger, said valve mechanism being arranged to beenergized through mechanism controlled by the braking mechanism of thecentrifugal.

12. A discharger mechanism for a sugar centrifugal embracing, arevoluble vertically movable discharger mounted in the centrifugalbasket, means for retarding and lifting the discharger, air actuatedpistons for causing, respectively, the retardation and the lifting ofthe discharger valve, mechanism for controlling a supply of compressedair to the respective pistons, including two valves operating inpredetermined sequence, one of them acting toenergize the pistons forretarding and for lifting the discharger upon the setting of the brakefor the centrifugal, the other valve controlling the raising andlowering of the lifting lever without lifting the discharger, saidvalves operating in alternation.

13. A discharger mechanism for asugar centrifugal embracing, a revolublevertically movable discharger device mounted in the centrifugal basket,means for retarding and for lifting the discharger, air actuated pistonsfor causing, respectively, "the retardation and the lifting of thedischarger, valve mechanism for controlling the admission of compressedair to the respective pistons comprising tWo alternately operatingvalves, one of which is controlled by means of the centrifugal controlmechanism, the other being controlled by the movements of the liftingpiston itself.

10 14. A discharger mechanism for sugar centrifugals embracing, arevoluble vertically movable discharger mounted in the centrifugalbasket, means for retarding and for lifting the discharger, air actuatedpistons ii) for causing, respectively, the retardation and the liftingof the discharger, valve mechanism controlling the supply of compressedair to the respective pistons comprising two alternately acting valveseach caus- 2 3 ing alternate strokes of the lifting piston, one of saidvalves being controlled by the centrifugal control mechanism, the otherbeing controlled by the up and down movement of the piston on eachalternate stroke 25 thereof.

In Witness whereof, I have subscribed the above specification.

EUGENE ROBERTS.

